Modular clean room enclosure

ABSTRACT

A portable, modular room enclosure having an open end providing horizontal, contaminant-free tunnel type laminar flow for surgery or the like includes mobile means for generating an air flow demountably connected to said enclosure, air supply means in the unit in communication with the air flow generating means for receiving the air flow and converting it to a contaminant-free horizontal laminar flow within the enclosure toward the open end, first and second partitions forming side walls of the enclosure, wherein each partition is demountably connected at one end to said air supply means and at least one retractable side panel slidably mounted on a track connected to each partition wherein the track and panel are in parallel relation with the partition. By extending or retracting the side panels the length of each partition may be selectively changed to accommodate the needs of a surgery theater or the like.

[ Nov. 27, 1973 MODULAR CLEAN ROOM ENCLOSURE Robert Claude Marsh,Albuquerque, N. Mex.

[75] Inventor:

Assignee: Bio-Dynamics, Inc., Castleton, Ind.

Filed: Mar. 10, 1972 Appl. No.: 233,453

OTHER PUBLICATIONS The Ii arr 121 /48 Clean Booth ProductlQataSh et,

Nlay 5, 1965, Laminar Flow Clean Room Handbook; Boyd Agnew, Jan. 1966,pages 2, 20 & 40.

Primary Examiner-William E. Wayner Attorney-W0odard, Weikart, Emhardt &Naughton [5 7] ABSTRACT A portable, modular room enclosure having anopen end providing horizontal, contaminant-free tunnel type laminar flowfor surgery or the like includes mobile means for generating an air flowdemountably connected to said enclosure, air supply means in the unit incommunication with the air flow generating means for receiving the airflow and converting it to a contaminant-free horizontal laminar flowwithin the enclosure toward the open end, first and second partitionsforming side walls of the enclosure, wherein each partition isdemountably connected at one end to said air supply means and at leastone retractable side panel slidably mounted on a track connected to eachpartition wherein the track and panel are in parallel relation with thepartition. By extending or retracting the side panels the length of eachpartition may be selectively changed to accommodate the needs of asurgery theater or the like.

1 Claim, 9 Drawing Figures PATENTED NOV 27 I975 SHEET 5 BF 5 1 MODULARCLEAN ROOM ENCLOSURE BACKGROUND OF THE INVENTION The invention relatesto a portable clean room and, in particular, to a surgery isolator as amovable, clean room enclosure providing a sterile, pathogen-freeenvironment for surgical operations needing sepsis control.

Infection of surgical wounds and microbial complications in otherhospital treatment areas still persist despite great advances inantiseptics during the past century. Additionally, modern implant andtransplant surgery and such specialized treatment as chemotherapy oftenplace fatal significance on hospital acquired sepsis. Airbornecontamination control has always been recognized as vital in controlingcross-infection within the hospital and is one of the first steps in theoverall sanitation program. Recently the requirements for ultra-clean orsterile assembly environments in the nuclear or space explorationindustries have lead to the development of clean rooms which canvirtually eliminate the environment as a source of airborne infection. I

Contemporary clean rooms are permanent structures generally enteredthrough air lock or the like and, as such, are not compatible withhospital surgery problems. Operating theaters and surgery rooms requirespecial equipment, such as X-ray equipment, gas fixtures and specialoperating lights. Therefore, a permanent clean room enclosure is notfeasible for a hospital as the requirements for a clean room will not beneeded for every operation. Accordingly there has developed a need for aportable enclosure for use with existing ceilings and fixtures in anoperating theater which will provide a clean room environment foroperations.

As employed in the present application the term clean room denotes afacility especially designed to create an atmosphere substantially freeof particles. For this purpose a maximum particle concentration of 100particles per cubic foot ).5 micrgnsand grea ter in sizejs required. Theterm laminar flow clean room as employed in the application is directedto an enclosure or room formed by a bank of high efficiency particulateair filters on one entire wall wherein air is introduced to theenclosure through the filter at a rate of from about 70 to l feet perminute. Conventional high efficiency particulate air (HEPA) filters havea minimum efficiency of 99.97 percent for particles as small as 0.3microns in size.

SUMMARY OF THE INVENTION It is, therefore, a primary object of theinvention to provide a portable, modular enclosure for use in operatingtheaters or the like which permits use of existing facilities andpermits free access for operating personnel.

It is another object of the invention to provide a modular clean roomenclosure having externally mounted support equipment to provide maximumavailable space within the enclosure. 7

It is an additional object of the invention to provide a modular cleanroom which is readily converted into a conventional operating theater,as desired.

, It is yet another object of the invention to provide a modular cleanroom which is freely open to personnel without the need for air locks orthe like.

It is a further object of the invention to provide a portable surgeryisolator whose length may be varied within predetermined limits in orderto adjust to the needs of different operations.

The above and other objects are met in a portable modular room enclosurehaving an open end providing horizontal, contaminant free, tunnel typelaminar flow for surgery or the like which includes mobile means forgenerating an air flow demountably connected to the enclosure. Airsupply means in the unit is in communication with the air flow generatorand receives the air flow and converts it to a contaminant-freehorizontal laminar flow towardthe open end of the enclosure. First andsecond partitions form side walls of the enclosure. Each partition isdemountably connected at one end to the air supply mechanism. At leastone retractable side panel is provided which is slidably mounted on atrack, wherein the track is connected to the partition. The track andpanel are mounted in parallel relation to the partition for selectivelyextending the length of the position. v

In one embodiment the modular enclosure includes a mounting base havingadjustable leveling feet. First and second air plenums, each plenumhaving a side opening and a front opening are adjacently seated on themounting base. First and second filter frame supports are boltedrespectively to the first and second air plenums. Each frame supportcarries a plurality of individual framed high efficiency particulate airfilters in snap locking engagement with the filter frame support.

- Each bank of I-IEPA filters is protected by a pair of punched screenslatched onto the frame support.

An air tower is provided on each side of the air plenum. Each air toweris equipped with a prefilter and blower for generating an air flow intothe plenum.

The sides of the portable clean room are formed by a pair of enclosurepanels attached to the side of a filter frame unit and singly anchoredto the ceiling. Each enclosure panel is provided with a pair of slidingglass door panels suspended from the floor. The glass door panels permitindividual adjustment of the sides of the isolator module.

If necessary, adjustable ceiling filler panels are provided on each sideenclosure wall and the filter frame support unit to prevent contaminatedair from entering the isolator immediately forward of the l-IEPA filterbank.

t Substantial significant advantages are obtained by the isolator. Theisolator is readily set up in existing operating theaters making use ofexisting ceilings and permitting use of existing lighting facilities,X-ray facilities, outlets and fixtures. Ready access through the openedend of the isolator is available without disturbing the integrity of theclean room environment. All available space within the clean roomenclosure is utilizable as the mechanical and electrical supportequipment remains outside the enclosure. If a clean room is not neededthe sliding glass sidewalls are retracted into the enclosure panel.

The adjustable ceiling filler panels permit the unit to be set up inrooms of varying heights within certain limits. Power cords, gas supplycords and monitoring circuit cords readily pass under the sliding doors.The transparent side panels permit a large audience to view theoperating theater within the room without the danger ofcross-contamination.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings illustrate asomewhat preferred embodiment of the invention in which:

FIG. I is a top plan view of the modular enclosure or isolatorillustrating the laminar flow of air through the unit;

FIG. 2 is a front view of the unit from the open end of unit toward thefilter bank;

FIG. 3 is a side view of the isolator with the corresponding air towerremoved and diagrammatically illustrating the ceiling anchor for theside wall;

FIG. 4 is a fragmentary, perspective view of a comer of the isolatorillustrating the adjustable filler panels;

FIG. 5 is an enlarged fragmentary view showing a ceiling hanger bracket;

FIG. 6 is a partial sectional view of an air tower of the unit adjacentthe side panel of the unit with the retractable glass sliding panelremoved;

FIG. 7 is a perspective view of the isolator with one pair of glassdoors retracted to the side wall;

FIG. 8 is a fragmentary, exploded view illustrating the connectionsbetween the track assembly carrying the sliding glass doors and the sidewall panel; and

FIG. 9 is an exploded view of a filter wall and air supply plenum of theunit.

DESCRIPTION OF PREFERRED EMBODIMENTS As illustrated in FIG. 1 modularenclosure or isolator 10 has associated therewith a pair of air towers12 for generating an air flow into the unit. Each air tower ismechanically connected to a plenum extension panel 14 to provide an airway into the unit. Air passing through the plenum extensions is receivedthrough the side openings 16 of air plenums 18. Each said air plenum 18opens into a bank 20 of high efficiency particulate air filters. Eachbank is protected by a pair of abutting perforated screens 22.

The wall of contaminant-free, laminar flow air represented by the solidline of arrows 24 in FIG. 1 is bounded and shaped by a pair of solidstationary partitions 26 connected to the sides of filter bank 20. Onepair of sliding glass door panels 28 is mounted to the exterior wall ofeach of the partitions 26. The bottom of the sliding glass door panelsis suspended above the floor to permit air and power lines and the liketo extend under the door panel. Air also passes over the tops of thedoor panels as well as from the end of the isolator 10. The aforesaidair passages are denoted by arrows in FIG. 1. This ultra clean airgently sweeps across the enclosure area removing all airbornecontaminants generated therein and also provides a positive barrieragainst particles from the surrounding environment.

As particularly illustrated in FIG. 6 air tower 12 is a self-containedmobile unit carried by a set of adjustable casters which provide aleveling adjustment to compensate for any possible uneven floor. Casters180 are spaced at each corner of the air tower. Tower 12 is formed froma rectangular shell 182. On the face of the shell are a pair ofelongated hinged corner panels 184 which provide access for a set ofthree vertically mounted prefilters 186, one set of prefilters to eachpanel. A pair of elongated slots 188 on the face of the air towerprovides an intake for the prefilters.

A pair of stacked blowers 30 draw air into the air tower and exhaust theair into an elongated rectangular discharge orifice 32. The blowers areshock mounted to reduce vibration.

Air is discharged from the air tower to discharge orifice 32 into amatched intake orifice 34 in plenum extension panel 14. In order toprovide a positive but detachable mechanical connection between airtower l2 and plenum extension panel 14 a rotatable mechanical latchingknuckle 36 is provided adjacent discharge orifice 32. The knuckle isoperated by means of crank 38 located on the face of the air tower.Latch knuckle 36 cooperates with horizontal bar 40 which is spacedacross plenum extension intake orifice 34.

Air tower 12 also contains gauge 42 for measuring air flow velocity andindicates a malfunction should one or both blowers fail to operateproperly. A ground chain loop 44 below air tower 12 provides a ground tothe conductor floor of the operating theater. In order to provide a morepositive and air tight seal between the air tower and plenum extensionpanel 14 a resilient, preferably Neoprene gasket 43 is provided aboutthe periphery of discharge opening 32. As illustrated in FIGS. 3 and 4in order to properly align air towers 12 with plenum extension panels 14there are provided a pair of docking stops 46 mounted at the top andbottom edges of intake orifice 34. As seen in FIG. 4 the stops extendoutwardly from the back edge of the extension panels 14 and engage therear panels 48 of air towers 12.

The isolator air supply and filter modules are shown in FIGS. 1, 2, 6, 7and 9. Air supply module 50 is formed from plenum extension panels 14and plenums 18. Filter module 52 is formed from filter bank 20 andprotective screens 22. Air supply module 50 and filter module 52 areseated on the walls 56 of mounting base 58. Mounting base 58 is arectangular frame containing six spaced apart leveling feet 60 as shownin FIG. 2. After the base has been leveled it is preferred to employ arubber or Neoprene gasket to seal the bottom of the mounting base to thefloor. A pair of rectangular air plenums 18 are seated side to sidealong the length of mounting base 58. Each plenum consists of agenerally rectangular frame with a solid rear and open front face. Thereis provided a side opening 16 in each of the plenum frames to receiveair passed from plenum extension panels 14 which is bolted on to theplenum. Air plenums 18 are each bolted to mounting base 58.

Filter module 52 is formed from a pair of filter frame support units 64bolted together side to side as illustrated in FIG. 9. If necessary asilicone sealant is provided between the bottom of each filter framesupport and the mounting base to provide an air tight seal therewith.

Each filter frame is divided into three compartments for retainingframed HEPA filters. For this purpose a spring loaded clamping mechanism66 is provided for each compartment. When necessary each framed I-IEPAfilter may be easily removed from the unit and replaced. Conventionalframed I-IEPA filters 68 are provided for each filter frame compartment,wherein each filter is adapted to remove all particulate matter 0.3microns and larger with an efficiency of 99.97 percent.

A pair of rectangular perforated screens 22 are latched to the front ofeach frame support 64. The perforated screens protect the HEPA filtersand also indicate damage to them. For present purposes it is preferredto employ perforated aluminum screens having a percent open area. Aworkable screen contains openings approximately 0.06 inch. in diameter.The screen is preferably about 1/16 inch thick. As shown in FIG. 9latches are provided on the upper face of frame support 64 and cooperatewith mounting hooks (not shown on the screen) to anchor the screen tothe frame support. Further, a series of spaced apart tongues 72 areprovided along the base of each frame support to cooperate with tonguereceiving grooves to further anchor the screens.

The screens cooperate with the filter bank to provide a unidirectionallaminar flow pattern directed toward the open end of the isolator and atpreferred velocity of from 70 to I10 and particularly 90 feet perminute.

The modular side enclosure units 74 are illustrated in FIGS. 3-8. Eachenclosure includes a solid aluminum partition 26 which is preferablycaulked or sealed with a silicone sealant to the floor of the operatingtheater. As shown in FIG. 6 each partition is bolted 76 to a side edgeof frame support 64. In order to carry glass door panels 28 each saidpartition is provided with a track assembly 78. FIG. 8 illustrates themounting of track assembly 78 to partition 26. An elongated stud plate80 is bolted or screwed to theoutside upper wall of the partition.

Four elongated threaded bolts '82 project horizontally from stud plate80. Each track assembly has a complimentary pair of pre-punched holesfor capture by each said bolt. A nut and washer 84 are employed toanchor each bolt on the track assembly.

As illustrated in FIG. 5 track assembly 78contains four extrudedrectangular compartments. The parallelly aligned bottom compartments 284are each provided with a pair of opposed channels 86 adapted to receivethe rollers associated with a conventional sliding door assembly.

For aesthetic purposes it is preferred to employ a pair of closureplates 88 to cover the track assembly. As shown in FIG. 8 rear insideclosure plate 89 is bolted to partition 26. Outer closure plate 90 isbolted to track assembly 78.

A second pair of closure plates 92 cover the assembly beyond thepartitions. The ends of closure plates 92 are screwed or bolted tomating flanges 94 on closure plates 88.

As illustrated in FIGS. 1, 3, 6 and 7 a pair of conventional glassdoorpanels 28 are hung on track assembly 78. Doors 28 are preferablysuspended about 3 inches off the floor so that operating room powerlines, gas lines and the like may pass safely thereunder. Each glassdoor panel assembly has a pair of parallelly aligned glass doorsconsisting of inner door 96 and outer door 98. A bumper 100 is providedto arrest the movement of inner door 96 adjacent plenum extension 14.Bumper 100 faces inner door 96 and is screwed to partition 26. A similarbumper 102 is screwed to the outer frame 104 of inner door 96 and servesto arrest the movement of outer door 98 as it is retracted.

outer door 96. In order to provide a further positive arrest for theoutward movement of the sliding doors a closure plate is screwed acrossthe ends of the track assembly (not shown).

In order to prevent scraping of the doors during opening and retractiona partition mounted roller guide 108 is provided to ease movementbetween the inner door and partitions. Similarly, a roller guide isprovided on the lower forward edge 110 at inner door 96 to preventscraping between the inner and outer doors.

In order to provide anair tight seal between the ceiling of theoperating room, the air supply module and the side partitions 26 fillerpanels are employed. Tuming now to FIGS. 4 and 7 there is shown a pairof partition mounted side filler panels 112. Each side filler panelextends from the rear edge 114 of each plenum 18 to the forward edge 116of each partition 26. Each filler panel 112 is formed from a lowerL-shaped bracket bolted to the top of partition 26 and an upper invertedL-shaped bracket which is frictionally mounted to lower bracket 118 bymeans of set screws 122. Upper bracket 120 is adapted to frictionallyslide along the outer surface of lower bracket 118 until the upperbracket engages the ceiling. At this point set screws 122 are engaged. Apair of upright extrusions 124 provide mounting brackets for the setscrews.

A Neoprene gasket is provided along the upper ledge of upper bracket 120to provide an air tight seal with the ceiling.

In similar fashion an upper 126 and lower 128 filler panel is providedalong the inner edge 130 of frame supports 64. A sealing gasket isprovided along the upper ledge of the upper filler panel 126 of theblankoff.

In order to support the weight of the glass doors in the extendedposition it is preferred to employ av track assembly mounted hangerbolt, as illustrated in FIGS. 3 and 5. For this purpose a bottom hangerbracket is screwed into the top compartments of track assembly 78 bymeans of machine screws 134. An inverted U- shaped top hanger bracket136 is slidably engaged along the rear wall 138 of lower bracket 132.For this purpose a pair of complimentary slots are provided in top andbottom hanger brackets 132, 136. A pair of screws 13 extend through themating slots and the height of top hanger bracket 136 is adjusted byselectively tightening the nuts on the screws in the desired position.

The top of top hanger bracket 136 contains a slot elongated in directionperpendicular to the mating slots 137 in the respective hanger brackets.For mounting purposes a hanger bolt 142 is driven into the operatingroom ceiling and permitted to extend the preselected distance below theceiling. The hanger bolt is captured by the slot in top hanger bracket136 and is engaged thereunder by a nut.

To assemble the surgery isolator mounting base 56 is moved to apreselected portion section of the operating theater and, if necessarycaulked or sealed to the floor. Depending on the length of the trackassemblies a hanger bolt 142 is driven into the ceiling for capture bythe respective hanger brackets. Air supply plenums 16 are bolted to themounting brackets and plenum extensions 14 are bolted to the respectiveends of plenum 16. With the air supply module 50 assembled, the filtermodule is then erected by bolting the frame support 64 to the airplenums 18. Next the partitions 26 are bolted to the filter support 64.The individual HEPA filters 68 are snapped into the respective filtersupport compartments and the perforated screens 22 are latched onto thefront of the frame supports. The track assembly and sliding doors arethen bolted to the respective side partitions. To support the trackassembly lower hanger bolt bracket 132 is slid along an extruded track144 on track assembly 18. When the hanger bolt 142 is suitably aligned apair of screws extending through the lower hanger bolt bracket aretightened locking the bracket onto the track assembly. The top hangerbracket is vertically adjusted until the hanger bolt extends through theslot in the top plate and then a nut is selectively tightened beneaththe slot to capture the hanger bolt.

Next, the side and top mounted ceiling filler panels are verticallyadjusted until they are in sealing engagement with the operating roomceiling. Silicone sealant is then applied to the juncture between thetop of the frame support unit and mounting base. Next, air towers 12 areindividually aligned with docking stops 46 on plenum extension 14. Afteralignment crank 38 on each of the air towers is actuated and mechanicallatch knuckle engages plenum bar 40 locking each respective air tower tothe plenum extension.

In general it is preferable to employ strong, rigid but lightweightmetals for the modular units. Aluminum is a preferred material.Preferably all components are desired to passed through a standarddoorway. If desired an additional air intake may be employed on top ofthe air tower.

While the preferred embodiment of the invention has been illustratedhereinabove it will be obvious to those skilled in that art that variousmodifications can be made in materials, size and mounting arrangementswithin the spirit of the invention. The invention is not to be limitedexcept as set forth in the following claims.

I claim:

1. A portable modular room enclosure having an open end providinghorizontal contaminant-free tunnel type laminar flow for surgery or thelike comprising:

a. mobile means for generating an air flow demountably connected to thesaid enclosure;

b. air supply means in said unit in communication with said air flowgenerating means for receiving said air flow and converting said flow toa contaminant free, horizontal laminar flow within said enclosure towardsaid open end;

c. first and second partitions forming side walls of said enclosure,each partition demountably connected at one end to said air supplymeans; and

d. at least one retractable side panel, slidably mounted on a trackconnected to each said partition, said track and panel in parallelrelation with said partition for selectively extending the length ofeach said partition.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,774,522 Dated November 27, 1973 Inventor) Robert Claude Marsh It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 2, line 20, "position" should read partition Column 7, line 8,"18" should read 78 Column 8, after line 28 insert the following claims:

2. The enclosure of claim 1 and further comprising at least oneadjustable filler panel rigidly attached to 4 a top portion of each ofsaid partitions and extending to a ceiling.

3. The enclosure of claim 2 in which said mobile means for generating anair flow comprises:

ashell having intake and exhaust openings therein; a prefilter mountedover each said intake opening; and

blower apparatus mounted within said shell to draw air into said shelland exhaust the air into said air supply means.

4. The enclosure of'claim 3 in which said air supply means comprises:-

a high efficiency particulate air filter apparatus mounted in a frame;

a plenum having an output opening coupled to' said filter apparatus andhaving an input opening; and

a plenum extension panel' having an output coupled to the input openingof said plenum and having an input coupled to-the exhaust opening ofsaid shell.

5. The enclosure of claim 4 in which said retractable side panel isslidably mounted on a track, said track and panel in parallel relationwith said partition. g

6. The enclosure of claim 5 and further comprising at least oneadjustable fillerpanel rigidly attached to a top portion of each of saidpartitions and extending to a ceiling.

FORM P0405) (10459) v uscoMM-Dc scan-Poe Y .5. GOYERNMENT PRINTINGOFFICE 1 I969 0-35533,

Patent No. 3 774 52 Dated Nmmmbfi: 2 1

Inventor-(s) I I Robert Claude Marsh It is certified that error appearsin the above-identified patent and that said Letters Patent are herebycorrected as shown below:

On the cover sheet, "1 Claim" should read 6 Claims-i.

Signed and'sealed this 20th day of August 1974.

(SEAL) Attest: I E E McMCOY M. GIBSON, JR. 0. MARSHALL DANN AttestingOfficer I Commissioner of Patents FORM Po-wso (10-69) USCOMWDC 50 m flUTS. GOVERNIIENT PRINTING OFFICE III 03"-3Sl.

1. A portable modular room enclosure having an open end providinghorizontal contaminant-free tunnel type laminar flOw for surgery or thelike comprising: a. mobile means for generating an air flow demountablyconnected to the said enclosure; b. air supply means in said unit incommunication with said air flow generating means for receiving said airflow and converting said flow to a contaminant free, horizontal laminarflow within said enclosure toward said open end; c. first and secondpartitions forming side walls of said enclosure, each partitiondemountably connected at one end to said air supply means; and d. atleast one retractable side panel, slidably mounted on a track connectedto each said partition, said track and panel in parallel relation withsaid partition for selectively extending the length of each saidpartition.